1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel in which a manufacturing process is simplified and method of manufacturing the same.
2. Description of the Background Art
Recently, as a flat panel display device, a plasma display panel (hereinafter, referred to as ‘PDP’) that can be easily made large attracts public attention. The PDP is adapted to display an image by controlling a gas discharge period of each of pixels according to digital video data. An example of a representative PDP is an AC type PDP that has three electrodes and is driven by alternate current (AC) voltage, as shown in FIG. 1, and is driven by an AC voltage.
FIG. 1 is a perspective view showing the configuration of a cell that is arranged on a typical AC type PDP in a matrix shape. FIG. 2 schematically shows the structure in which electrodes of an upper substrate of the AC type PDP are arranged.
Referring to FIG. 1 and FIG. 2, the cell of the PDP includes an upper plate having a pair of sustain electrodes 14 and 16, an upper dielectric layer 18 and a protection film 20, all of which are sequentially formed on an upper substrate 10; and a lower plate having an address electrode 22, a lower dielectric layer 24, barrier ribs 26 and a phosphor layer 28, all of which are sequentially formed on a lower substrate 12. In the above, the upper substrate 10 and the lower substrate 12 are spaced apart from each other in parallel by means of the barrier ribs 26.
The sustain electrode 14 includes a transparent electrode 14A that has a relatively wide width and is formed using a transparent electrode material (ITO) through which a visible ray can pass, and a metal electrode 14B for compensating for a resistance component of the transparent electrode 14A. Meanwhile, the sustain electrode 16 includes a transparent electrode 16A that has a relatively wide width and is formed using a transparent electrode material (ITO) through which a visible ray can pass, and a metal electrode 16B for compensating for a resistance component of the transparent electrode 16A. In this time, the metal electrodes operate as bus electrodes. This pair of the sustain electrodes is composed of the scan electrode 14 and the sustain electrode 16 depending on a pulse applied thereto. The scan electrode 14 is mainly supplied with a scan pulse for scanning a panel and a sustain pulse for maintaining discharging. The sustain electrode 16 is mainly supplied with the sustain pulse.
The upper dielectric layer 18 and the lower dielectric layer 24 are accumulated with electric charge upon discharging.
The protection film 20 serves to prevent damage of the upper dielectric layer 18 due to sputtering and to increase emission efficiency of secondary electrons. The protection film 20 is typically formed using magnesium oxide (MgO).
The address electrode 22 is formed in a way to intersect the pair of the sustain electrodes 14 and 16. This address electrode 22 is supplied with a data pulse for selecting cells to be displayed.
The barrier ribs 26 are formed parallel to the address electrode 22 and serve to prevent ultraviolet generated by the discharging from leaking toward neighboring cells.
The phosphor layer 28 is coated on the lower dielectric layer 24 and the barrier ribs 26 and emits any one visible ray of red, green and blue lights.
Further, an inert gas for discharging a gas is injected into discharge spaces.
A method of manufacturing the upper substrate of the plasma display panel constructed above will now be described.
FIG. 3 is a view shown to explain a conventional method of manufacturing the upper substrate of the PDP.
A black electrode paste 33 is printed on a transparent electrode 32, i.e., an upper substrate 31 in which an ITO electrode is formed by means of a screen method, and is then dried (FIG. 3a).
Thereafter, a first ultraviolet is exposed to the black electrode paste 33 through a first photomask 34 (FIG. 3b). It is preferred that the photomask 34 is patterned so that the first ultraviolet is exposed only to the black electrode paste 33 located between discharge cells. Thus, the first ultraviolet is exposed only to the black electrode paste 33 located between the discharge cells, thereby hardening only the exposed portion. A black matrix for precluding light generated from one discharge cell from transmitting to neighboring discharge cells is formed at the exposed portion.
Meanwhile, a silver electrode paste 35 is printed on the exposed black electrode paste 33 by means of a screen-printing method (FIG. 3c). A second ultraviolet is exposed to the silver electrode paste 35 through a second photomask 36 (FIG. 3d). At this time, it is preferred that the second ultraviolet has a light source having a wavelength that can harden not only the silver electrode paste 35 but also the black electrode paste 33 printed below the silver electrode paste 35, through the second photomask 36. The second photomask 36 is preferably patterned so that the silver electrode paste 35 located over the transparent electrode 32 is hardened.
After the corresponding electrode pastes 33 and 35 are hardened by the second ultraviolet as described above, the upper substrate 31 is developed to form a predetermined bus electrode 37 and a black matrix 38. A dry and sintering process are then performed (FIG. 3e). At this time, the bus electrode 37 has a silver electrode 37b and a black electrode 37a. 
Thereafter, a dielectric paste is printed on the upper substrate 31 on which the bus electrode 37 is formed and is then dried, thus forming a predetermined dielectric layer 39. Thereby, the upper substrate of the plasma display panel is completed (FIG. 3f).
In the conventional method of manufacturing the upper substrate of the plasma display panel, when the bus electrode is formed, the processes of printing, drying and exposing the black electrode paste and the silver electrode paste are needed twice. Therefore, there is a problem in that the process is very complicated. Further, there is a problem in that additional cost is spent in terms of a manufacturing process.